Development of Recombinant PLC-Zeta Protein as a Therapeutic Intervention for the Clinical Treatment of Oocyte Activation Failure.

The sperm-specific phospholipase C zeta (PLCζ) protein is widely considered as the predominant physiological stimulus for initiating the Ca2+ release responsible for oocyte activation during mammalian fertilization. The increasing number of genetic and clinical reports that directly link PLCζ defects and/or deficiencies with oocyte activation failure (OAF) necessitates the use of a powerful therapeutic intervention to overcome such cases of male factor infertility. Currently, in vitro fertilization (IVF) clinics treat OAF cases after intracytoplasmic sperm injection (ICSI) with Ca2+ ionophores. Despite their successful use, such chemical agents are unable to trigger the physiological pattern of Ca2+ oscillations. Moreover, the safety of these ionophores is not yet fully established. We have previously demonstrated that recombinant PLCζ protein can be successfully used to rescue failed oocyte activation, resulting in efficient blastocyst formation. Herein, we produced a maltose binding protein (MBP)-tagged recombinant human PLCζ protein capable of inducing Ca2+ oscillations in mouse oocytes similar to those observed at fertilization. Circular dichroism (CD) experiments revealed a stable, well-folded protein with a high helical content. Moreover, the recombinant protein could retain its enzymatic properties for at least up to 90 days after storage at -80 °C. Finally, a chick embryo model was employed and revealed that exposure of fertilized chicken eggs to MBP-PLCζ did not alter the embryonic viability when compared to the control, giving a first indication of its safety. Our data support the potential use of the MBP-PLCζ recombinant protein as an effective therapeutic tool but further studies are required prior to its use in a clinical setting.

Sperm induce a secondary increase in ATP levels in mouse eggs that is independent of Ca2+ oscillations.

Egg activation at fertilization in mouse eggs is caused by a series of cytosolic Ca2+ oscillations that are associated with an increase in ATP concentrations driven by increased mitochondrial activity. We have investigated the role of Ca2+ oscillations in these changes in ATP at fertilization by measuring the dynamics of ATP and Ca2+ in mouse eggs. An initial ATP increase started with the first Ca2+ transient at fertilization and then a secondary increase in ATP occurred ∼1 h later and this preceded a small and temporary increase in the frequency of Ca2+ oscillations. Other stimuli that caused Ca2+ oscillations such as PLCz1 or thimerosal, caused smaller or slower changes in ATP that failed to show the distinct secondary rise. Sperm-induced Ca2+ oscillations in the egg also triggered changes in the fluorescence of NADH which followed the pattern of Ca2+ spikes in a similar pattern to oscillations triggered by PLCz1 or thimerosal. When eggs were loaded with low concentrations of the Ca2+ chelator BAPTA, sperm triggered one small Ca2+ increase, but there were still extra phases of ATP increase that were similar to control fertilized eggs. Singular Ca2+ increases caused by thapsigargin were much less effective in elevating ATP levels. Together these data suggest that the secondary ATP increase at fertilization in mouse eggs is not caused by increases in cytosolic Ca2+. The fertilizing sperm may stimulate ATP production in eggs via both Ca2+ and by another mechanism that is independent of PLCz1 or Ca2+ oscillations.

COVID-19 Vaccination Personas in Syria: Evidence from a Cross-Sectional Survey.

Achieving a high level of COVID-19 vaccination coverage in a conflict-affected setting is challenging. The objective of this paper is to shed further light on the main determinants of vaccination coverage using a large, cross-sectional sample (October-November 2022) of over 17,000 adults in Syria. We find evidence that certain demographic and socioeconomic characteristics describe a core set of vaccination personas. Men, older respondents, and those who are more educated and trust information received from healthcare authorities are more likely to be vaccinated. Healthcare workers in this sample are highly vaccinated. Furthermore, respondents with more positive views towards COVID-19 vaccines are also more likely to be willing to be vaccinated. By contrast, respondents who believe that vaccines are associated with significant side effects are also more likely to refuse vaccination. In addition, younger respondents and women, as well as those with a lower level of education, are more likely to refuse to be vaccinated. Respondents with a neutral attitude towards vaccines are also more likely to be undecided, whereas respondents who are refusing to get vaccinated are more likely to trust the information received from private doctors, private clinics, as well as social media and, more broadly, the internet.

Olvanil activates sensory nerve fibers, increases T cell response and decreases metastasis of breast carcinoma.

BACKGROUND: Inactivation of sensory neurons expressing transient receptor potential vanilloid 1 (TRPV1) enhances breast cancer metastasis. Sensory neurons have profound effects on immune response to a wide range of diseases including cancer. Hence, activation of sensory nerves using feasible approaches such as specific TRPV1 agonists may inhibit breast cancer metastasis through neuroimmune pathways. TRPV1 agonists are considered for the treatment of pain and inflammatory diseases. METHODS: We here first determined the effects of four different TRPV1 agonists on proliferation of three different metastatic breast carcinoma cells since TRPV1 is also expressed in cancer cells. Based on the results obtained under in-vitro conditions, brain metastatic breast carcinoma cells (4TBM) implanted orthotopically into the mammary-pad of Balb-c mice followed by olvanil treatment (i.p.). Changes in tumor growth, metastasis and immune response to cancer cells were determined. RESULTS: Olvanil dose-dependently activated sensory nerve fibers and markedly suppressed lung and liver metastasis without altering the growth of primary tumors. Olvanil (5 mg/kg) systemically increased T cell count, enhanced intra-tumoral recruitment of CD8+ T cells and increased IFN-γ response to irradiated cancer cells and Con-A. Anti-inflammatory changes such as increased IL-10 and decrease IL-6 as well as S100A8+ cells were observed following olvanil treatment. CONCLUSIONS: Our results show that anti-metastatic effects of olvanil is mainly due to activation of neuro-immune pathways since olvanil dose used here is not high enough to directly activate immune cells. Furthermore, olvanil effectively depletes sensory neuropeptides; hence, olvanil is a good non-pungent alternative to capsaicin.

The causality of borrowing: Lexical loans in Eurasian languages.

All languages borrow words from other languages. Some languages are more prone to borrowing, while others borrow less, and different domains of the vocabulary are unequally susceptible to borrowing. Languages typically borrow words when a new concept is introduced, but languages may also borrow a new word for an already existing concept. Linguists describe two causalities for borrowing: need, i.e., the internal pressure of borrowing a new term for a concept in the language, and prestige, i.e., the external pressure of borrowing a term from a more prestigious language. We investigate lexical loans in a dataset of 104 concepts in 115 Eurasian languages from 7 families occupying a coherent contact area of the Eurasian landmass, of which Indo-European languages from various periods constitute a majority. We use a cognacy-coded dataset, which identifies loan events including a source and a target language. To avoid loans for newly introduced concepts in languages, we use a list of lexical concepts that have been in use at least since the Chalcolithic (4000-3000 BCE). We observe that the rates of borrowing are highly variable among concepts, lexical domains, languages, language families, and time periods. We compare our results to those of a global sample and observe that our rates are generally lower, but that the rates between the samples are significantly correlated. To test the causality of borrowing, we use two different ranks. Firstly, to test need, we use a cultural ranking of concepts by their mobility (of nature items) or their labour intensity and "distance-from-hearth" (of culture items). Secondly, to test prestige, we use a power ranking of languages by their socio-cultural status. We conclude that the borrowability of concepts increases with increasing mobility (nature), and with increased labour intensity and "distance-from-hearth" (culture). We also conclude that language prestige is not correlated with borrowability in general (all languages borrow, independently of prestige), but prestige predicts the directionality of borrowing, from a more prestigious language to a less prestigious one. The process is not constant over time, with a larger inequality during the ancient and modern periods, but this result may depend on the status of the data (non-prestigious languages often remain unattested). In conclusion, we observe that need and prestige compete as causes of lexical borrowing.

Presence of S100A8/Gr1-Positive Myeloid-Derived Suppressor Cells in Primary Tumors and Visceral Organs Invaded by Breast Carcinoma Cells.

BACKGROUND: Increased S100A8/A9 expression in Gr1-positive cells has been shown in myeloid-derived suppressor cells and may play a role in the formation of a metastatic milieu. We aimed to determine S100A8/A9 expression alone and with coexpression of Gr1 (a myeloid marker) in primary tumor and visceral tissues invaded by metastatic breast carcinoma. MATERIALS AND METHODS: Female BALB/c mice were injected with 4TLM, 4THM, and 67NR orthotopically. Confluent cells (75%-80%) were used. Primary tumor, lung, liver, and spleen tissue samples were removed 26 days after injection. Peripheral blood smears and metastasis assay were performed, as was immunohistochemistry and staining. RESULTS: S100A8/A9 immunoreactivity alone or coexpressed with Gr1 was found in primary tumors formed by 4TLM and 4THM cells, which was markedly higher than in primary tumors formed by nonmetastatic 67NR cells. Similarly, liver and lung tissues obtained from mice injected with 4TLM or 4THM cells were invaded by S100A8/A9-positive and Gr1-positive cells. Double-positive cells were markedly fewer in liver and lung tissues of animals injected with 67NR cells. S100A8/A9-positive cells were mostly localized in red pulp of spleens. We observed an increased number of neutrophils in the peripheral blood of mice injected with metastatic breast carcinoma cells. CONCLUSION: Tumor-derived factors may increase S100A8/A9-positive cells locally and systemically, and S100A8/A9-positive cells may provide an appropriate milieu for the formation of metastasis.